Maj Sjöwall (Swedish pronunciation: [maj ˈɧø̂ːval]; 25 September 1935 – 29 April 2020) was a Swedish author and translator. She is best known for her books about police detective Martin Beck. She wrote the books in collaborative work with her partner Per Wahlöö.

Maj Sjöwall was the daughter of Margit Trobäck and CEO Will Sjöwall.^[1]

After completing school Sjöwall was employed at Åhlén & Åkerlunds publishers between 1954 and 1959, Wahlström & Widstrands publishers between 1959 and 1961 and then Esselte publishers between 1961 and 1963.^[2]

Sjöwall was best known for the collaborative work with her partner Per Wahlöö on a series of ten novels about the exploits of Martin Beck, a police detective in Stockholm.^[3] They also wrote several novels separately.^[4] In 1971, the fourth of the Beck books, The Laughing Policeman (a translation of Den skrattande polisen, originally published in 1968) won an Edgar Award from the Mystery Writers of America for Best Novel; the book was also adapted into the film The Laughing Policeman starring Walter Matthau.^[3] In 2013, Sjöwall received the fifth Lenin Award.^[5]

After the death of Wahlöö, she continued working as a translator, writing columns for magazines and as an author.^[6] With Danish author Bjarne Nielsen she in 1989 published the book Dansk Intermezzo.^[7] In 1990, she and author Tomas Ross published the thriller Kvinnan som liknade Greta Garbo.^[8]

Sjöwall married her first husband, magazine editor Gunnar Isaksson, in 1955, and they divorced in 1958.^[1] She married again in 1959 to photographer Hans J. Flodquist; they divorced in 1962.^[1]

Sjöwall had a 13-year relationship with Wahlöö, which lasted until his death in 1975.^[9]

Sjöwall died on 29 April 2020, at the age of 84 after a prolonged illness.^[10]